Thursday, April 6, 2017

How to make a kalimba using the lathe

I made this kalimba (aka thumb piano) using a few scrap pine wood pieces I had in my workshop.

I begun by drawing a circle with my compass on a piece of pine and cutting it out on the bandsaw.

I then mounted the wooden circle on a face plate and turned it true on the lathe. I used mostly the bowl gouge for this job.

I then used a skew chisel and a spindle gouge, to create a mortise at the bottom of my piece. This way I can mount the piece on my chuck.

The body of my kalimba is actually a mini wooden bowl.

I used wood filler to fill any imperfections on the wood and then sanded it.

I reversed the piece on my chuck and used the bowl gouge and a spindle gouge to hollow my bowl.

To make the top of my kalimba, I split a piece of pine on the bandsaw. I then mounted my hand plane upside down on my vise and used it as a jointer to joint the two book matched pieces of my top. I then glued the two pieces together.

I used the bowl as guide to mark the circle I needed and cut it out on the bandsaw. I also used my disc sander to sand both edges of my top smooth.

I opened up the sound hole of the top, using a hole saw on my drill press.

I glued the top on my bowl. After the glue dried, I remounted the kalimba on the lathe and turned the top flush with the body, using a spindle gouge and sandpaper.

To make the kalimba’s metal keys I needed a springy steel material. I used an old hacksaw blade for this job. I cut it to size with my angle grinder.

To create a finger rest on my keys, I heated the metal to red hot with my blow torch and then using a hammer and my vise’s anvil I forged the edge to expand the shape of the steel. I then shaped all the keys to my likeness on my grinding wheel.

I used the angle grinder again to cut a metal rod to size.

I used a file to flatten one edge of the rod. On my drill press I drilled two holes, while using oil to prevent my drill bit from overheating.

I then shaped a scrap piece of niangon wood on my disc sander to make my kalimba’s bridge. I also cut two big nails to size using my angle grinder. I glued them in place with two part epoxy glue. Before that I used a V chisel to open two V grooves. This way the nails would sit in place while the epoxy dried.

I then predrilled, screwed and glued the bridge in place.

I applied 8 coats of clear, glossy varnish from a spray can. I sanded between coats with 300 grit to achieve a better finish.

My kalimba has 5 keys. This way I can tune it to a pentatonic scale. I used a guitar tuner to tune it. When you increase the length of the key you get a lower note. Decrease it and you get higher pitch.